>I don't think Csound is actually public domain. I think the original
>copyright is still in force. Correct me, Vercoe or ffitch, if I'm wrong!

I'm neither of these gentlemen, but I recently had a conversation
with Barry on this issue.  I'll try to explain it to the best
of my understanding.  Disclaimer, I'm not a lawyer, and not 
employed by MIT's Office of Intellectual Property (thank heavens).
If you really want to push on the edges of the Csound license,
you should consult a lawyer and talk to MIT directly about it.

Csound is not in the public domain.  The source code is provided
as a service to the community and is freely usable for personal,
educational, or research purposes.  Thus, the extensions and
add-ons that have been developed are well within the spirit of
the Csound license, and the Media Lab encourages continued 
development as a research and music-making tool.

What you *can't* do is embed public Csound or reuse code from
public Csound in a commercial product.  The license does not 
give you permission to do this.  Thus, the Csound license is
more restrictive than GPL, which explicitly allows commercialization
as long as any extensions are also GPL'ed.  The "derivative
products" clause means that MIT would also frown upon trying
to take a signficant chunk of the public Csound code and 
use it to build some other sort of system, even if it weren't
for sale.  But as long as it is still Csound, add-ons
and improvements are welcome.

Selling music or other sounds made with Csound is permissible.  
Selling other tools that interoperate with Csound is also 
permissible.  The restrictions only apply to the Csound source 
code itself.  

The reason for restrictions on commercial application is that 
certain Media Lab sponsors have given money to us in exchange 
for exclusive commercial rights.  If we allowed anyone else to 
commercialize the Csound code, it would violate the contracts
that we signed with those sponsors.

Our SAOL implementation is released until a different 
agreement -- we've placed that code in the public domain,
and you can do anything you want with it, including sell it
to your neighbors or re-use it in products.  It's important
restrictions that we must unfortunately continue to apply 
to Csound.

Best,
 
  -- Eric

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|  Eric Scheirer  |A-7b5 D7b9|G-7 C7|Cb   C-7b5 F7#9|Bb  |B-7 E7|
|eds@media.mit.edu|      < http://sound.media.mit.edu/~eds >
|  617 253 0112   |A A/G# F#-7 F#-/E|Eb-7b5 D7b5|Db|C7b5 B7b5|Bb|
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